/* Professional UI system */
:root {
	--brand-primary: #0f3d91;
	--brand-secondary: #0b7a75;
	--brand-accent: #2f9e44;
	--brand-ink: #101828;
	--brand-muted: #475467;
	--brand-border: #e4e7ec;
	--brand-surface: #ffffff;
	--brand-bg: #f5f7fb;
	--brand-soft: #eef2f6;
}

* { box-sizing: border-box; }
body {
	font-family: "Segoe UI", Tahoma, Geneva, Verdana, sans-serif;
	background: var(--brand-bg);
	color: var(--brand-ink);
	line-height: 1.7;
}

a { text-decoration: none; }

/* Navbar */
.navbar { box-shadow: 0 12px 30px rgba(16, 24, 40, 0.12); }
.site-nav {
	background: linear-gradient(120deg, var(--brand-primary), #1c5bd6) !important;
}
.site-nav .nav-link { color: #e6edff !important; font-weight: 600; }
.site-nav .nav-link:hover { color: #ffffff !important; }
.site-nav .btn { background: #ffffff; border: none; color: var(--brand-primary); }
.site-nav .btn:hover { filter: brightness(0.98); }
.brand-logo { height: 36px; width: auto; display: inline-block; }
.navbar-brand { font-weight: 800; letter-spacing: 0.2px; }

@media (min-width: 992px) {
	.nav-overlay { display: none; }
}

@media (max-width: 991.98px) {
	.nav-overlay {
		position: fixed;
		inset: 0;
		background: rgba(15, 23, 42, 0.5);
		backdrop-filter: blur(2px);
		opacity: 0;
		visibility: hidden;
		transition: opacity 0.2s ease;
		z-index: 1030;
	}
	body.offcanvas-open .nav-overlay {
		opacity: 1;
		visibility: visible;
	}

	.offcanvas-collapse {
		position: fixed;
		top: 0;
		right: 0;
		bottom: 0;
		width: 280px;
		padding: 1.25rem 1.25rem 2rem;
		background: #ffffff;
		box-shadow: -12px 0 30px rgba(0, 0, 0, 0.12);
		transform: translateX(100%);
		opacity: 0;
		visibility: hidden;
		pointer-events: none;
		transition: transform 0.35s ease, opacity 0.25s ease;
		z-index: 1040;
		overflow-y: auto;
		display: flex;
		flex-direction: column;
	}
	.offcanvas-collapse.collapse {
		display: block;
	}
	body.offcanvas-open .offcanvas-collapse,
	.offcanvas-collapse.show {
		transform: translateX(0);
		opacity: 1;
		visibility: visible;
		pointer-events: auto;
	}
	.offcanvas-collapse .nav-link { color: #0f172a !important; }
	.offcanvas-collapse .nav-link:hover { color: var(--brand-primary) !important; }
	.offcanvas-collapse .btn { width: 100%; justify-content: center; }
	.offcanvas-collapse .navbar-nav { gap: 0.35rem; }
	.offcanvas-header {
		padding-bottom: 0.5rem;
		border-bottom: 1px solid #e2e8f0;
	}
}

/* Container spacing */
main.container { max-width: 1200px; }

/* Cards */
.card {
	border: 1px solid var(--brand-border);
	border-radius: 16px;
	background: var(--brand-surface);
	box-shadow: 0 18px 45px rgba(16, 24, 40, 0.08);
	transition: transform 0.2s ease, box-shadow 0.2s ease;
}
.card:hover { transform: translateY(-2px); box-shadow: 0 22px 50px rgba(16, 24, 40, 0.12); }
.card-title { font-weight: 700; }

/* Buttons */
.btn {
	border-radius: 12px;
	font-weight: 600;
	padding: 0.5rem 1rem;
	transition: all 0.15s ease;
}
.btn:hover { transform: translateY(-1px); }
.btn-cta {
	background: linear-gradient(135deg, var(--brand-accent), #4dd17b);
	color: #ffffff;
	border: none;
	box-shadow: 0 12px 24px rgba(47, 158, 68, 0.3);
}
.btn-cta:hover { color: #ffffff; filter: brightness(0.98); }
.btn-outline-secondary { border-color: var(--brand-border); color: var(--brand-muted); }

/* Badges & chips */
.badge { font-weight: 700; }
.chip {
	display: inline-flex;
	align-items: center;
	gap: 8px;
	padding: 6px 12px;
	border-radius: 999px;
	background: #e8f0ff;
	color: #1d4ed8;
	font-weight: 700;
	font-size: 0.85rem;
}

/* Alerts & forms */
.alert { border: 1px solid var(--brand-border); border-radius: 12px; }
.form-control, .form-select {
	border-radius: 12px;
	border-color: var(--brand-border);
	padding: 0.6rem 0.8rem;
}
.form-control:focus, .form-select:focus {
	border-color: #a7c7ff;
	box-shadow: 0 0 0 0.2rem rgba(74, 122, 255, 0.15);
}

/* Tables */
.table {
	border-color: var(--brand-border);
}
.table thead th {
	background: #f2f6ff;
	color: #334155;
	font-weight: 700;
}

/* Progress */
.progress { height: 12px; background: #eef2f6; border-radius: 999px; }

/* Dashboard hero */
.dashboard-hero {
	background: linear-gradient(135deg, #0f3d91, #1c5bd6);
	color: #ffffff;
	border-radius: 18px;
	padding: 26px 28px;
	box-shadow: 0 24px 55px rgba(15, 61, 145, 0.35);
}
.dashboard-hero h1 { font-size: 1.8rem; font-weight: 800; margin: 0 0 6px; }
.dashboard-hero p { margin: 0; opacity: 0.92; }

/* List groups */
.list-group-item { border-color: var(--brand-border); }

/* Scrollbar */
::-webkit-scrollbar { width: 8px; height: 8px; }
::-webkit-scrollbar-track { background: #eef2f6; }
::-webkit-scrollbar-thumb { background: #cbd5e1; border-radius: 6px; }
::-webkit-scrollbar-thumb:hover { background: #94a3b8; }

/* Subject selection cards */
.subject-card {
	transition: all 0.2s ease-in-out;
	background: #fff;
	cursor: pointer;
}
.subject-card:hover {
	transform: translateY(-4px);
	box-shadow: 0 16px 40px rgba(30,115,190,0.2) !important;
	border-color: var(--brand-primary) !important;
}
.subject-card .card-body {
	padding: 24px 16px;
	background: linear-gradient(135deg, rgba(30,115,190,0.04), rgba(82,163,74,0.04));
}

/* Flashcards */
.flashcards-grid {
	display: grid;
	grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
	gap: 18px;
}
.flashcard {
	background: transparent;
	perspective: 1000px;
	cursor: pointer;
}
.flashcard-inner {
	position: relative;
	width: 100%;
	min-height: 220px;
	transform-style: preserve-3d;
	transition: transform 0.6s;
}
.flashcard.is-flipped .flashcard-inner {
	transform: rotateY(180deg);
}
.flashcard-front,
.flashcard-back {
	position: absolute;
	inset: 0;
	backface-visibility: hidden;
	border-radius: 14px;
	padding: 22px;
	box-shadow: 0 10px 32px rgba(0,0,0,0.18);
	background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
	color: #fff;
	font-weight: 600;
	display: flex;
	align-items: center;
	justify-content: center;
	text-align: center;
	direction: rtl;
	line-height: 1.7;
	font-size: 1.02rem;
}
.flashcard-back {
	transform: rotateY(180deg);
	background: linear-gradient(135deg, #f093fb 0%, #f5576c 100%);
}
.flashcard-front .MathJax,
.flashcard-back .MathJax,
.flashcard-front mjx-container,
.flashcard-back mjx-container {
	direction: ltr;
	unicode-bidi: isolate;
	display: inline-block;
	text-align: center;
	margin: 0 4px;
}
.flashcard-front mjx-container[display="true"],
.flashcard-back mjx-container[display="true"] {
	display: block;
	text-align: center;
	margin: 8px 0 0;
}

/* Force LaTeX (MathJax/KaTeX) to LTR site-wide */
.MathJax,
mjx-container,
.katex {
	direction: ltr;
	unicode-bidi: isolate;
	text-align: left;
}
.katex-display {
	direction: ltr;
	unicode-bidi: isolate;
	text-align: center;
}

/* Resource Cards */
.resources-horizontal-scroll {
	display: flex;
	gap: 16px;
	overflow-x: auto;
	overflow-y: hidden;
	padding: 8px 0;
	margin-bottom: 24px;
	scroll-behavior: smooth;
}
.resources-horizontal-scroll::-webkit-scrollbar {
	height: 6px;
}
.resources-horizontal-scroll::-webkit-scrollbar-track {
	background: #eef7f1;
	border-radius: 3px;
}
.resources-horizontal-scroll::-webkit-scrollbar-thumb {
	background: var(--brand-secondary);
	border-radius: 3px;
}
.resources-horizontal-scroll::-webkit-scrollbar-thumb:hover {
	background: var(--brand-primary);
}
.resource-card {
	display: flex;
	flex-direction: column;
	align-items: center;
	justify-content: center;
	padding: 32px 16px;
	background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
	border-radius: 12px;
	color: white;
	text-decoration: none !important;
	transition: all 0.2s ease-in-out;
	min-height: 180px;
	min-width: 160px;
	flex-shrink: 0;
	box-shadow: 0 10px 28px rgba(15,41,77,0.06);
}
.resource-card:hover {
	transform: translateY(-4px);
	box-shadow: 0 14px 32px rgba(102, 126, 234, 0.3);
}
.resource-card.resource-card-pdf {
	background: linear-gradient(135deg, #f093fb 0%, #f5576c 100%);
}
.resource-card.resource-card-pdf:hover {
	box-shadow: 0 14px 32px rgba(245, 87, 108, 0.3);
}
.resource-card.resource-card-audio {
	background: linear-gradient(135deg, #4facfe 0%, #00f2fe 100%);
}
.resource-card.resource-card-audio:hover {
	box-shadow: 0 14px 32px rgba(79, 172, 254, 0.3);
}
.resource-card.resource-card-flashcard {
	background: linear-gradient(135deg, #43e97b 0%, #38f9d7 100%);
}
.resource-card.resource-card-flashcard:hover {
	box-shadow: 0 14px 32px rgba(67, 233, 123, 0.3);
}
.resource-card.resource-card-video {
	background: linear-gradient(135deg, #fa709a 0%, #fee140 100%);
}
.resource-card.resource-card-video:hover {
	box-shadow: 0 14px 32px rgba(250, 112, 154, 0.3);
}
.resource-card.resource-card-youtube {
	background: linear-gradient(135deg, #ff0000 0%, #ff6b6b 100%);
}
.resource-card.resource-card-youtube:hover {
	box-shadow: 0 14px 32px rgba(255, 0, 0, 0.3);
}
.resource-card.resource-card-mindmap {
	background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
}
.resource-card.resource-card-mindmap:hover {
	box-shadow: 0 14px 32px rgba(102, 126, 234, 0.3);
}
.resource-card.resource-card-link {
	background: linear-gradient(135deg, #a8edea 0%, #fed6e3 100%);
	color: #333;
}
.resource-card.resource-card-link:hover {
	box-shadow: 0 14px 32px rgba(168, 237, 234, 0.3);
}
.resource-card.resource-embed {
	min-width: 320px;
	min-height: 240px;
	padding: 16px;
	align-items: stretch;
}
.resource-card.resource-embed .resource-label {
	font-size: 15px;
	font-weight: 700;
	margin-bottom: 10px;
}
.resource-embed-frame {
	position: relative;
	width: 100%;
	padding-top: 56.25%;
	border-radius: 12px;
	overflow: hidden;
	background: rgba(255, 255, 255, 0.2);
}
.resource-embed-frame iframe {
	position: absolute;
	inset: 0;
	width: 100%;
	height: 100%;
	border: 0;
}
.resource-icon {
	font-size: 40px;
	margin-bottom: 12px;
}
.resource-label {
	font-weight: 600;
	font-size: 14px;
	text-align: center;
	margin-bottom: 8px;
	line-height: 1.3;
	word-break: break-word;
	overflow-wrap: break-word;
}
.resource-action {
	font-size: 12px;
	opacity: 0.95;
	font-weight: 500;
	margin-top: auto;
}

/* Mindmap */
.mindmap-canvas {
	border: 1px solid #e8eef6;
	border-radius: 12px;
	min-height: 420px;
	overflow: hidden;
	background: #fff;
	padding: 8px;
}
.mindmap-canvas svg {
	max-width: 100%;
	height: auto;
}


.profile-card {
      background: #f5f5f5;
      border-radius: 14px;
      padding: 20px;
    }

.profile-img {
	width: 90px;
	height: 90px;
	border-radius: 50%;
	object-fit: cover;
	filter: grayscale(100%);
	transition: 0.3s ease;
	border: 2px solid #ddd;
}

/* Optional hover effect */
.profile-img:hover {
	filter: grayscale(0%);
}
.social a {
	color: #555;
	font-size: 1.2rem;
	margin-left: 10px;
	transition: 0.2s;
}

.social a:hover {
	color: #000;
}